I know when laying laminate floor or engineered wood floor they say leave an expansion gap-but read one site where a floor laying expert said it was all a con to sell expensive beading.
Is this true any experts on here?

reason i ask is i would like some nice engineered or even decent laminate flooring like i had in old house ( think i had something like click lock 9000 from allied carpets) and i want it in my hallway-now being a hallway it is only about 1 m in parts but obviously long, be so much faster and easier to lay if i could get away without taking skirting boards of and associated problems that brings,now if i could just allow say 1mm cutting allowance on sides i could fill that with a bead of silicone or similar but leave an expansion gap at either end and hide that under the joining pieces under door.

We always leave an expansion, ideally hidden under the skirting, either by putting the skirt on after or by under cutting the skirting.
I have seen a cheap laminate fitted tight to a room, the room was empty, and the floor ballooned up in the middle. once trimmed to allow a 10mm expansion it returned to flat. so yes I would always allow an expansion.

We always leave an expansion, ideally hidden under the skirting, either by putting the skirt on after or by under cutting the skirting.
I have seen a cheap laminate fitted tight to a room, the room was empty, and the floor ballooned up in the middle. once trimmed to allow a 10mm expansion it returned to flat. so yes I would always allow an expansion.

I know it looks better under skirting but such a pain to remove , then in removing chances are bits of plaster will come off etc, but beading looks naff tho

Beading will never look as good, but if you're not happy to remove the skirt, it is prob your option.
Undercutting needs specialist tooling, may be possible to hire? either a Karlton skirt/door trimmer or an oscillating saw such as a Fein Multimaster.

FFF just got on knees and you are possibly right-i can see very tiny nail holes-so tiny that paint almost fills them-anyway-will skirting just pull of easy then? with minimal effort and no plaster coming off-will it just have gripfill on top edge to smooth things off? so there is no gaps at top

FFF just got on knees and you are possibly right-i can see very tiny nail holes-so tiny that paint almost fills them-anyway-will skirting just pull of easy then? with minimal effort and no plaster coming off-will it just have gripfill on top edge to smooth things off? so there is no gaps at top

grip fill should not be on top edge, that will be caulking (painters mate) just run a "stanley knife" on top of skirting and it "should" come away from wall without plaster coming off